Error when multiple filter with the same name are given for kn trigger

[rhuss]

In kn trigger --filter type=bla --filter type=blub, "blub" will silently win. As this is very likely not the user's intent, an error should be thrown instead.

Same btw for "kn service create --env". The check could be part of a unified list-option handling.

[duglin]

to be clear, you mean that while --filter and --env are additive, multiple occurrences of the flag builds up a list, if the values within the list contain repeats of the "key" (e.g. filter type or env name) then we should consider alerting the user, right?

[rhuss]

Exactly, if you put the same key on the same CLI call like in kn trigger create bla --filter type=foo --filter type=bar. Currently type=foo is just ignored as its overwritten by type=bar. IMO an error should be given instead, as this very likely not what the users wants (and provided both options by accident).

[MIBc]

I'd like to try.